Suppose you have a separation process one mile deep: How can you
use the pressure to your advantage in filtration or even distillation?

In filtration, you usually apply vacuum on the filtrate side of the
filter to speed it up. Only a pressure differential, not a high
pressure on both sides, will help you there. Same for reverse osmosis,
which couples normal osmotic pressure due to a chemical potential
difference across a semi-permeable membrane with an extra applied
pressure ONLY on the high-concentration side, to shift equilibrium. If
you had a reverse osmosis process under water, you would have a higher
pressure on both sides of the membrane, which wouldn't help you at all.
As far as water purification by distillation, high pressure is not
going to help you either because you are usually trying to remove
non-volatile components (salts, metals). This means at high pressure,
you'll just have to pump more heat into the water to get it to
vaporize. Elevated pressure is useful for many distillations, but
certainly the cost of building, operating, and maintaining an
underwater facility is much more than any energy cost to generate high
pressure in the column on land...

In short, desalination and water purification plants are already
located where they're most economical - on land and next to a source of
water.

Quote:

I am thinking of water purification, actually.
Someone (a p-chem prof, actually) had once told me something about
there actually being a voltage drop (caused by pressure difference)
when you go that deep under water?

Huh? Voltage drop? There's a lot of pressure due to the sheer weight of
the water, and it's not a pressure drop. Just pressure.

I have one single question regarding the handling of salicylic acid. This
acid is a very volatile fine powder, which easily adsorb on skin, leading to
unwanted irritation. It also tends to agglomerate and is quite impossible to
solubilize afterwards. So we spread it manually through a mesh onto our
formula, which is the hardener of a high-solids epoxy.
My question is the following : how can one handle it safely, i.e. without
skin irritation ? Does someone have any idea about that ?
Best regards.

If you must sprinkle it over a large area... electrostatic platen. No
dust gets loose. Remember the megaohm resistors lest the high voltage
arc.

<mshawjr@frontiernet.net> wrote in message news:J6qTf.1038$tT.939@news01.roc.ny...

Quote:

Man I have found this site that has the cheapest ink for any printer.
You can compare prices and then review the companies on service and
quality. <http://www.imagraphix.com> Let me know what you think

Why are spammers always so transparent? These things are always the same.

Sorry guys. The spam stuff was not my intent. I do oppoligies and won't
happen again. I have never been on newsgroups before and not sure how to
work them. I hope you guys can forgive a bad choice. Murphey
BS. For a new guy you managed to hit every single, non related NG I

subscribe to. You are not a beginner any more than I am Mother
Theresa.
-
Regards
Gordie

Sorry guys. The spam stuff was not my intent. I do oppoligies and
won't
happen again. I have never been on newsgroups before and not sure
how to
work them. I hope you guys can forgive a bad choice. Murphey
BS. For a new guy you managed to hit every single, non related NG I
subscribe to. You are not a beginner any more than I am Mother
Theresa.
-
Regards
Gordie

Sorry guys. The spam stuff was not my intent. I do oppoligies and won't
happen again. I have never been on newsgroups before and not sure how to
work them. I hope you guys can forgive a bad choice. Murphey
BS. For a new guy you managed to hit every single, non related NG I
subscribe to. You are not a beginner any more than I am Mother
Theresa.

seek tubing that won't corrode in strong solutions of Lithium Chloride,
but conducts heat very well. For service in auto/truck exhaust
temperatures.

Corrosion resistance will also depend on whether there is oxygen
(early and middle transition metals vanish), carbon monoxide (middle
and late transition metals vanish), or hydrogen (ferrous
embrittlement) present. Will there be contamination by transition
metal ions like iron or copper? Pitting!

Sintered beryllium oxide, silicon carbide, or alumina come to mind.
Hastelloy C-2000. Oh yeah... Is this Enviro-whiner spew or does the
cost matter?